This application is the national stage of International Application No. PCT/EP97/06925, filed on Dec. 11, 1997.
The invention relates to a device for generating active oxygen ions in the air for improving air, in particular breathing air, comprising at least one air ionizer and one electrical transformer generating a sufficient high voltage for air ionization.
Healthy breathing air is described as air without substantial parts of noxious gases or noticeable, in many cases unpleasant odorous substances. Healthy inhaled air is to contain a number as low as possible of bacteria, viruses and other germs, which is very important, in particular when knowing the fact that annually more than 40,000 people become sick with fatal results in Germany by airborne infections, for example in hospitals, in restaurants, and in means of mass transport, as was determined by a scientific study of the Robert-Koch-institute (Bundesgesundheitsblatt Issue 7/96, Page 246). The cost of these nosocominal infections are estimated by the authors to be more than 3 billion German Marks. odorous materials drastically reduces the comfort, the condition and the capability to concentrate and thus the life quality of the exposed human being. It can be easily realized that for example the stink of kerosene and other engine exhaust gases renders impossible the tasting of delicious meals or at least substantially reduces the taste in restaurants, for example at airports or close to the road, because the gustatory nerves and the olfactory nerves are blocked to such an extent by the base load of stink that they are unable to perceive any shades. It is also known that the continuous presence in highly charged air renders tired and fatigued. Human beings, which have to work in bad air make after some time significantly more errors as compared to human beings, which work in problem-free air. It is also known that electrostatic charges are generated to an increased extent, if the air present in the room is poor in ions or, respectively, where positively charged ions or negatively charged ions dominate. Such air, commonly designated as xe2x80x9celectrically chargedxe2x80x9d exerts uncontested influence on the vegetative nervous system. Furthermore, damages of electronic apparatus and data carriers can occur based on static charges. In addition, the level of sick people in enterprises, which are not able to offer good breathing air to their coworkers based on bad functioning air conditioning plants, is substantially higher as the level of sick people of enterprises, where attention is paid to perfect air.
The passengers in a motor vehicle are annoyed and at times damaged in their health based on the exhaust gases of other motor vehicles. The journal xe2x80x9cScientistxe2x80x9d, issue September 1996, cites in this context a Danish investigation, according to which the risk to become sick with lung cancer is for bus drivers 50 percent higher than in a comparison group of persons. Sensible known steps for reducing the emissions of passengers of motor vehicles are for example sensor controlled ventilation systems, wherein the inflow of outer air is stopped always then and switched to circulating operation, when the vehicle reaches a zone of increased contaminant concentration. Furthermore active carbon filters are known and are employed, which have a limited retaining capacity relative to some gases and vapors and of course dust and pollen. Larger concentrations however cannot be retained by the filters. In addition, there exist filter passing gases such as for example the poisonous carbon monoxide and finest dust and soot, such as are given off for example by diesel motors, which are considered to be cancer promoting.
In general the known ionization apparatuses are furnished with a hand operated switch, with the aid of which taps at transformers can be switched with the effect, that different voltages are fed to the ionization tube in order to be able to adjust in this fashion the power of ionization. Such an arrangement can operate substantially satisfactorily, if it is a purpose, for example to hold the number of germs small in a cold storage depot, because in general no substantially varying air contamination with other atmospheric pollutants occurs in a cold storage depot. However, the concentration of the air impurities varies substantially in nearly all other applications and possibly in a ratio of 1 to 10,000.
A fixedly set ionization apparatus cannot lead to a satisfactory solution in these cases, because either the ionization power is insufficient and thereby the smells and germs are not effectively combated or however in case of ionization powers set to a high level contaminant load appear interfering in case of a low air contamination by smellable and possibly dangerous ozone concentrations.
It is an object of the present invention to create an apparatus for the physical processing of air, in particular of breathing air, which corresponding to the load of the air with smelling materials or exhaust gases is capable to perform an ionization of the air depending on the concentration of the smelling materials or exhaust gases. One of the essential technical problems comprises, to adapt the ionization power of the recited ionization apparatus such that on the one hand an effective combating of smells and germs is furnished and on the other hand however, no excess ozone concentration should be generated thereby.
The solution of this object comprises an apparatus of the initially recited kind, wherein the air ionizer is coupled to a sensor, which sensor determines the contents of the air in oxidizable gases (air quality sensor) and based on the determined contents of such oxidizable gases, the fed in electrical energy is changeable by way of an electric control device such that in case of low concentrations of oxidizable gases only a low ionization power is furnished, which can be increased controlled by a sensor and automatically with increasing concentration of oxidizable gases to a maximum value.
According to a further embodiment of the invention, an ion counter disposed after the air ionizer detects the number of the ions present in the air and acts through an electric circuit such onto the device or, respectively, the air ionizer, that in case of a low ion number the ionization power of the air ionizer is increased sensor controlled and automatic, and preferably continuously, and in case of a high ion number the ionization power of the air ionizer is decreased sensor controlled and automatic, and preferably continuously. Thus the control of the ionization power of the air ionizer is connected according to the gas load of the air, in particular of the breathing air.
The transformer exhibits various winding taps for changing the controlled power of the air ionizer and the transformer can be controlled through the winding taps such that, effect correctly and sensor controlled, a higher or lower operating voltage of the air ionizer results. In a similar way a chain of capacitive resistors or ohmic resistors can be switched in front of the air ionizer for changing the drive power of the air ionizer, wherein the chain of capacitive resistors or ohmic resistors is such bridged by suitable switching members of an appropriate effect, that an adapted, controlled ionization power of the air ionizer results according to the bridging. The appropriate effect and situation adapted change of the ionization power can also be achieved by having a plurality of air ionizers present and operating, wherein the active area of the operating air ionizers is adapted to the requirements determined by the air quality sensor or air quality sensors based on suitable electrical switching members. The increase of the ionization power occurs controlled by a sensor always then, when the change of the gas concentration detected by the air quality sensor exhibits a certain quotient over time. Or, the increase of the ionization power of the air ionizer can also then occur controlled by a sensor, where the gas depending value of the air quality sensor or the quotient from the value change of the air quality sensor over a time period exceeds a certain value.
According to a further embodiment the apparatus or, respectively the air ionizer is predisposed or integrated into an air humidifier.
An ozone sensor follows to the air ionizer for expanding the application spectrum, wherein the ozone sensor is connected to the electrical control circuit and wherein the ozone sensor acts onto the electrical control circuit upon determination of a certain ozone content in the air, wherein the electrical control circuit decreases the electrical energy fed to the air ionizer. A driving with a saw-tooth shaped voltage can be performed in case of an occurrence of ozone for controlling the electrical energy fed to the air ionizer, wherein the saw-tooth shaped voltage is reduced to such voltage upon reaching of a voltage permitting ozone production, at which voltage on the one hand a safe ionization occurs, but on the other hand however, still no ozonization occurs. This saw tooth shaped voltage can oscillate back and forth within a voltage band between the two voltage levels and can be formed like a ramp or formed like a saw tooth.
According to an advantageous embodiment the air ionizer comprises two or several electrically contacting planar or plate shaped structured bodies as electrodes, which are disposed in parallel planes and opposite to each other and which are electrically separated from each other by a dielectric and which form a planar capacitor, wherein a sufficiently high alternating voltage is applied to the electrodes for ionizing the air.
Furthermore, the air ionizer can comprise a planar outer electrode and a planar inner electrode, which are enclosed hermetically by a dielectric carrying the outer electrode, wherein the outer electrode and the inner electrode in each case are contacted by the electrical connection, and wherein an electrical alternating voltage sufficiently high for the ionization of air is connected to the inner electrode and to the outer electrode.
A plurality of flat air ionizers (flat ionizer) are stacked to a stack or to several stacks electrically isolated from each other, which stacks are passed through by the air to be treated, wherein a sufficiently high electrical alternating voltage is applied the individual electrodes for ionizing air. The inner electrodes can assume the same electrical potential as the neighboring flat ionizers or the inner electrodes can exhibit an electrical potential unequal to the neighboring flat ionizers.
According to an advantageous embodiment the air ionizer is permeable to air, wherein the two planar electrodes exhibit breakouts and are structured like a grid or like a hole, and wherein the air to be ionized flows through the free cross-section of the electrodes. One of the electrodes comprises an electrically conducting filtering material, which filtering material is grid like and electrically insulated surrounded by the other electrode; and the air to be treated flows through both electrodes.
At least one of the electrodes exhibits a plurality of needles or tips directed against the counter electrode in order to increase the corona effect.
A stack of ionization plates is disposed in a ventilation channel and fills the complete cross-section of the ventilation channel, and thereby forms and air ionizer, wherein the ionizer plates are aligned either with the narrow side front face, or with their cross-sectional face passable by the air toward the flow of air. Such an apparatus can be incorporated into an air channel transporting outside air of a motor vehicle.